Coumarins and Hesperetin Inhibit Human Respiratory Syncytial Virus Infection

Area of Science:

• Virology
• Natural Product Chemistry
• Drug Discovery

Background:

• Respiratory syncytial virus (RSV) causes severe lower respiratory tract infections in vulnerable populations.
• Current treatments for RSV are limited, necessitating the exploration of novel antiviral agents.

Purpose of the Study:

• To investigate the potential of natural compounds, specifically coumarins and flavonoids, as antiviral agents against RSV.
• To evaluate the efficacy of coumarins and hesperetin in inhibiting RSV replication in various cell cultures.

Main Methods:

• Cytotoxicity testing of coumarins and hesperetin on A549, HEp-2, and HBE cells.
• Analysis of anti-RSV activity in cell cultures infected with RSV-luc or rgRSV.
• Encapsulation of compounds using beta-cyclodextrin to enhance permeability and solubility.

Main Results:

• Esculetin and 4-methyl demonstrated effective inhibition of rgRSV in A549 and HEp-2 cells.
• Encapsulated coumarin, esculetin, and hesperetin showed inhibition against rgRSV in HBE cultures.
• Coumarins effectively inhibited RSV replication and penetrated mucus barriers in HBE cultures.

Conclusions:

• Coumarins exhibit significant antiviral activity against RSV in cell culture models.
• Beta-cyclodextrin encapsulation is crucial for improving coumarin cell permeability and efficacy.
• Natural coumarins represent a promising therapeutic avenue for managing RSV infections.